2. Reference solution

2.1. Travel

Displacements in the center of solid \(A\) are imposed in the directions \(x\) and \(y\) depending on time. The trips are of the form:

\[\]

left{

begin {aligned} D_x =sum_ {i}omega_ {x_i} sin (2pi f_ {x_i} t)\ D_y =sum_ {i}omega_ {y_i} sin (2pi f_ {y_i} t) end {aligned}

right.

2.2. Uncertainty about solutions

It is a test case of non-regression. We test for non-regression.